1. Field of the Invention
The present invention relates to a silyl compound, a light emitting material, and an organic light emitting device using the same.
2. Description of the Related Art
An organic light emitting device is a device which includes a thin film containing a fluorescent organic compound interposed between an anode and a cathode, which generates an exciton from the fluorescent compound by injection of an electron and a hole from each electrode, and which utilizes light to be irradiated when the exciton returns to a ground state.
Japanese Patent Application Laid-Open No. H08-12600 discloses a phenylanthracene derivative and an organic light emitting device using the derivative as examples of a material containing an anthracene ring and an organic light emitting device using the material. The document describes that, particularly when the derivative is used as a blue light emitting material or as an electron injecting or transporting material, a good organic film can be formed because the derivative has low crystallinity. However, none of the luminous efficiency and durable lifetime of the organic film is sufficient for practical use.
Japanese Patent Application Laid-Open No. H09-157643 and Japanese Patent Application Laid-Open No. H10-72579 disclose an aminoanthracene derivative and a diaminoanthracene derivative, respectively. The documents each describe that the use of each of the derivatives as a light emitting material can provide green light emission. However, the luminous efficiency of a device using each of the derivatives is low, and the durable lifetime of the device is not sufficient for practical use.
Japanese Patent No. 3,008,897 discloses a device using a specific bianthryl compound as a light emitting material, and describes that the device can emit light with high luminance. However, the document has no description concerning the luminous efficiency or durable lifetime of the device. Japanese Patent Application Laid-Open No. H11-8068 discloses a device using a specific anthracene compound containing an olefin site as a light emitting material, and describes that the device can emit light having a color ranging from a yellow color to a red color. However, the luminous efficiency of the device is not sufficient for practical use.
Japanese Patent Application Laid-Open No. 2001-284050 discloses a device containing an anthracene derivative with a specific structure, an electron transporting compound, and another fluorescent compound in a light emitting medium layer, to thereby provide a red light emitting device with improved reliability. However, the device has insufficient luminous efficiency for practical use.
Japanese Patent Application Laid-Open No. H03-271296 discloses an anthracene compound having a diarylamino group and a silyl group as a charge transport material in an electrophotographic photosensitive member. However, the document has no description concerning the application of the compound to an organic light emitting device.